Food allergies are mysterious. We still don’t know why some people develop allergies to certain foods and others do not. We can’t pinpoint why there are more cases of food allergies than ever before either.
Yet another interesting fact about food allergies has arisen from a recent survey of the population in India. The results, which were published in the journal Allergy, found that 24 common foods cause sensitization in more than one-quarter of the population, a rate much higher than what is seen in Europe or North America.
The EuroPrevall study, led by the European Commission, set out to look at the prevalence and cost of food allergies across Europe, but was expanded to other parts of the world. Most recently the results of the EuroPrevall INCO study were published. This survey included a sample of over 11,000 residents of South India. These people answered a questionnaire, and then more than 500 were selected for a more detailed survey and testing for food sensitization and allergies.
The results of the study were fascinating in that the researchers found that 26.5 percent of the population showed sensitization to one or more of the 24 most common foods in India. That rate is incredibly high, compared to rates of about 16 percent in Europe and 13 to 16 percent in the U.S. Also unusual was that while so many people were found to be sensitive to foods, only about 1.2 percent had actual clinical reactions, or allergic reactions, to the foods.
Sensitive to Foods vs. Allergic
When a person is shown to be sensitive to foods, it means that he has tested positive for those food allergies but shows no clinical signs. In other words, he does not have an allergic reaction to that food when eaten. A reaction to an allergen is a response of the immune system. For example, if your child is allergic to peanuts, her immune system produces an antibody specific to a peanut protein. When she eats peanuts, these antibodies are produced and go on the attack.
Someone may show sensitization to an allergen like peanuts, which means that the body is producing the antibodies. However, sensitization does not always lead to a reaction. What the recent research found was that a lot of people in India, one-quarter of the population, produces antibodies to certain foods but doesn’t have the allergic reaction.
Why Sensitization, But Few Reactions?
This latest study has uncovered a very interesting fact. So far, Indians seem to have the highest rates of sensitization to foods in the world, and yet very few allergies. The researchers conclude that they are somehow protected from allergic reactions. Something about the lifestyle or diet is protective. The researchers also caution that as diets and lifestyles change in India, including a move toward more junk food and foods with preservatives, they could lose this protection from allergies.
The survey included participants from the city of Bangalore, and the residents there are becoming more westernized in their diets and lifestyles. The researchers worry that this transition could lead to an explosion of food allergies. All those people who are sensitized to certain allergens have the potential to become allergic. The foods that showed the highest rates of sensitivity were shrimp and sesame.
Is a Western Lifestyle to Blame?
Food allergies are on the rise, and nowhere is this truer than in western countries like the U.S. and Western Europe. Although no one knows for sure why this is true, there have been many suggestions, like the fact that we are very clean and have too little exposure to germs, but there are probably many factors. What we know for sure is that as other cultures become westernized, they may also begin to see more food allergies.
Evidence like the most recent study from India gives further proof that something about our western lifestyle is leading us to have more food allergies. It helps us to better understand how allergies work and why we get them. More work needs to be done, of course, but every new study like this one is another piece of the puzzle.